The use of metaphor by prophets of the Catholic Charismatic Renewal movement is discussed, focusing on prophesies made at the movement's 1975 annual conference in Rome, where prophets revealed that the movement's purpose was to protect the church from the forces of evil. In a subsequent prophecy, another prophet revealed that it was God's will that members of the Charismatic Renewal band together to form a bulwark against the onslaught of the forces of the Enemy. The bulwark metaphor is said to be dependent on a genre convention in the performance of prophecy, i.e., the use of performative speech acts, progressing from commissive to declarative to assertive; to the extent that prophetic utterance is heard as the definitive word of God, prophecy carries its own guarantee of performative felicity and predicative success. It is suggested that the metaphor of the bulwark and others like it constitute a critical link between prophecy as an arbiter of social practice and as an ongoing discourse. (LLBA 1998, vol. 32, n. 5)